1. Field of the Invention
The present invention relates to an electric discharge lamp device, the light source of which is an electric discharge lamp, in which the electric discharge lamp is directly connected with a circuit device for generating a high voltage to operate the electric discharge lamp.
2. Description of the Related Art
An electric discharge lamp device, the light source of which is an electric discharge lamp, is used for a headlight for vehicle use. In order to operate the electric discharge lamp, it is necessary to impress a high voltage upon the electric discharge lamp. Therefore, the electric discharge lamp is electrically connected with a circuit means, or circuit device, for generating a high voltage by a high voltage wire.
However, in the structure of connecting the electric discharge lamp with the circuit means device by the high voltage wire, it is necessary to shield the high voltage wire so as to prevent noise being generated by the high voltage wire. Further, in order to connect the high voltage wire with the electric discharge lamp, it is necessary to provide a high voltage connector. Accordingly, the manufacturing cost of the electric discharge lamp device is raised.
In order to solve the above problems, it is possible to use a structure in which the high voltage wire is not used and the electric discharge lamp and the circuit device are directly connected with each other to accomplish the electric connection as disclosed in Japanese Unexamined Patent Publication No. 10-228804. When the electric discharge lamp and the circuit device are directly connected with each other, it becomes unnecessary to use the high voltage connector and the high voltage wire.
However, when the electric discharge lamp and the circuit device are directly connected with each other and the circuit device is arranged close to the electric discharge lamp, the inner temperature of the circuit device is raised by the influence of conduction or radiation of heat generated by the electric discharge lamp and also by the influence of heat generated by the circuit device itself. Accordingly, there is a possibility of malfunction of circuit elements incorporated into the circuit device.
Further, according to Japanese Unexamined Patent Publication No. 10-228804, there is provided a bracket protruding from a rear face of the reflector of the electric discharge lamp, and the circuit device is supported by an end portion of the bracket. However, in this structure, heat generated by the electric discharge lamp stays around the circuit device because the bracket is arranged at an upper and a lower position of the circuit device. Accordingly, the temperature of the circuit device is significantly raised.
An object of the present invention is to provide an electric discharge lamp device from which a high voltage wire and a high voltage connector are removed so that a temperature rise in the circuit device can be prevented by a simple structure.
According to the electric discharge lamp device of the first aspect of the present invention, an electric discharge lamp and a circuit device for impressing a high voltage upon the electric discharge lamp are directly connected with each other so that they are electrically connected. Accordingly, it becomes unnecessary to provide a high voltage connector and a high voltage wire for connecting the electric discharge lamp with the circuit device.
The structure of the electric discharge lamp device of the first aspect of the present invention will be described as follows. There is formed a gap between a face of the circuit device, which is opposed to the reflecting member, and the reflecting member. This gap formed between the face of the circuit device, which is opposed to the reflecting member, and the rear face of the reflecting member continues to a space formed by the reflecting member and the case. Accordingly, air rises when it is heated by the influence of heat generated by the electric discharge lamp and the circuit device. This rising air is not obstructed by the circuit device. Therefore, the thus heated air quickly moves upward. Accordingly, heat is not accumulated in a gap formed between the reflecting member and the circuit device. After the thus heated air has risen, the peripheral air flows into the gap by convection.
When a profile of the circuit device opposed to the reflecting member is restricted, it is possible to cool the circuit device by a simple structure and prevent the temperature of the circuit device from rising.
The structure of the electric discharge lamp device of the first aspect of the present invention will be described as follows. There is formed a gap between a face of the circuit means, which is opposed to the reflecting member, and the reflecting member. This gap formed between the face of the circuit means, which is opposed to the reflecting member, and the rear face of the reflecting member continues to a space formed by the reflecting member and the case. Accordingly, air rises when it is heated by the influence of heat generated by the electric discharge lamp and the circuit means. This rising air is not obstructed by the circuit means. Therefore, the thus heated air quickly moves upward. Accordingly, heat is not accumulated in a gap formed between the reflecting member and the circuit means. After the thus heated air has risen, the peripheral air flows into the gap by convection.
When a profile of the circuit means opposed to the reflecting member is restricted, it is possible to cool the circuit means by a simple structure and prevent the temperature of the circuit means from rising.
According to the second aspect of the present invention, the electric discharge lamp device includes: an attaching section protruding to the right and left from the circuit means; and a boss section, which is arranged in the reflecting member, protruding onto the attaching section side so that the boss section can be positioned to the attaching section, wherein the circuit means can be fixed to the reflecting means when the attaching section and the boss section are positioned to each other. Since the attaching section and the boss section are arranged so that the circulation of air in a gap formed between the reflecting member and the circuit means can not be obstructed, air which has been heated by the heat generated by the electric discharge lamp and the circuit means can quickly goes up in the gap between the reflecting member and the circuit means. Accordingly, it
According to the second aspect of the present invention, the electric discharge lamp device includes an attaching section protruding to the right and left from the circuit device and a boss section, which is arranged in the reflecting member, protruding onto the attaching section side of the reflecting member. In this configuration the boss section can be positioned adjacent to the attaching section so that the circuit device can be fixed to the reflecting means member. Since the attaching section and the boss section are arranged so that the circulation of air in a gap formed between the reflecting member and the circuit device is not obstructed, air which has been heated by the heat generated by the electric discharge lamp and the circuit device can quickly enter the gap between the reflecting member and the circuit device. Accordingly, it is possible to positively prevent a rise in the temperature of the circuit device.
According to the electric discharge lamp device of the third aspect of the present invention, a distance between the reflecting member and the circuit device is not less than 6 mm on the upper side of the connecting section at which the electric discharge lamp is connected with the circuit device. Therefore, the width of a passage for air can be ensured. Air, heated by the electric discharge lamp, and the circuit device, moves upward and into the passage. Accordingly, air can be quickly circulated by convection, and the circuit device can be effectively cooled.